A technique improves pattern features formed by etching and the uniformity of the features across the surface of a substrate. An etching method includes steps a), b), c), d), and e). Step a) includes placing, on a support, a substrate including a target film. Step b) includes partially etching the target film and forming a recess. Step c) includes setting the temperature of the support at a first temperature, and forming, on a sidewall of the recess, a first film having a first film thickness distribution. Step d) includes partially further etching the target film having the first film formed on the target film. Step e) includes setting the temperature of the support at a second temperature different from the first temperature, and forming, on the sidewall of the recess, a second film having a second film thickness distribution different from the first film thickness distribution.
Legal claims defining the scope of protection, as filed with the USPTO.
1. An etching method, comprising: a) placing a substrate on a support, the substrate including a target film; b) partially etching the target film and forming a recess therein by a plasma generated from a first gas; c) setting a temperature of the support at a first temperature after performing the partial etching, and forming a first film on a sidewall of the recess by introduction of a second gas different from the first gas, the first film having a first film thickness distribution; d) partially further etching the target film after the first film has been formed on the recess of the target film by a plasma generated from a third gas different from the second gas; and e) setting the temperature of the support at a second temperature different from the first temperature after the partially further etching, and forming a second film on the sidewall of the recess by introduction of a fourth gas different from the third gas, the second film having a second film thickness distribution different from the first film thickness distribution.
2. The etching method according to claim 1 , wherein the second temperature is higher than the first temperature.
3. The etching method according to claim 2 , wherein the forming the first film comprising: adjusting a temperature of a first zone of the support corresponding to a first area of the substrate to a temperature different from a temperature of a second zone of the support corresponding to a second area of the substrate to form the first film in the first area to have at least one of a thickness or a position different from a thickness and a position of the first film formed in the second area.
4. The etching method according to claim 3 , wherein the first area includes a center of the substrate, and the second area includes an edge of the substrate.
5. The etching method according to claim 4 , wherein c) includes c-1) supplying a first reactant and causing the first reactant to be adsorbed on the side wall of the recess, and c-2) supplying a second reactant and causing the second reactant to react with the first reactant to form the first film, e) includes e-1) supplying a third reactant and causing the third reactant to be adsorbed on the sidewall of the recess, and e-2) supplying a fourth reactant and causing the fourth reactant to react with the third reactant to form the second film, and c-2) is performed for a duration different from a duration of e-2) so as to form the first film to have at least one of a thickness or a position different from a corresponding thickness or position of the second film.
6. The etching method according to claim 5 , wherein the first film thickness distribution varies in at least one of a thickness direction or a radial direction of the substrate.
7. The etching method according to claim 5 , wherein the second film thickness distribution varies in at least one of a thickness direction or a radial direction of the substrate.
8. The etching method according to claim 7 , wherein the target film includes a silicon-containing layer.
9. The etching method according to claim 8 , wherein the substrate includes a carbon-containing mask on the target film.
10. The etching method according to claim 1 , wherein the forming the first film further comprising: adjusting a temperature of a first zone of the support corresponding to a first area of the substrate to a temperature different from a temperature of a second zone of the support corresponding to a second area of the substrate to form the first film in the first area to have at least one of a thickness or a position different from a thickness and a position of the first film formed in the second area.
11. The etching method according to claim 10 , wherein the first area includes a center of the substrate, and the second area includes an edge of the substrate.
12. The etching method according to claim 1 , wherein the first film thickness distribution varies in at least one of a thickness direction or a radial direction of the substrate.
13. The etching method according to claim 1 , wherein the second film thickness distribution varies in at least one of a thickness direction or a radial direction of the substrate.
14. The etching method according to claim 1 , wherein the target film includes a silicon-containing layer.
15. The etching method according to claim 1 , wherein the substrate includes a carbon-containing mask on the target film.
16. The etching method according to claim 1 , further comprising: repeating b), c), d), and e) until the recess has an aspect ratio of at least 40.
17. The etching method according to claim 1 , wherein the first film and the second film have a same composition.
18. An etching method, comprising: a) placing a substrate on a support the substrate including a target film; b) partially etching the target film and forming a recess therein; c) setting a temperature of the support at a first temperature, and forming a first film on a sidewall of the recess, the first film having a first film thickness distribution: d) partially further etching the target film after the first film has been formed on the recess of the target film; and e) setting the temperature of the support at a second temperature different from the first temperature, and forming a second film on the sidewall of the recess, the second film having a second film thickness distribution different from the first film thickness distribution wherein c) includes c-1) supplying a first reactant and causing the first reactant to be adsorbed on the sidewall of the recess, and c-2) supplying a second reactant and causing the second reactant to react with the first reactant to form the first film, e) includes e-1) supplying a third reactant and causing the third reactant to be adsorbed on the sidewall of the recess, and e-2) supplying a fourth reactant and causing the fourth reactant to react with the third reactant to form the second film, and c-2) is performed fir a duration different from a duration of e-2) so as to form the first film to have at least one of a thickness or a position different from a corresponding thickness or position of the second film.
19. An etching method, comprising: a) placing a substrate on a support, the substrate including a target film; b) partially etching the target film and forming a recess therein by a plasma generated from a first gas; c) setting temperatures of at least two of a plurality of zones of the support to different temperatures after performing the partial etching, and forming a film on a sidewall of the recess by introduction of a second gas different from the first gas, the film having different film thickness distributions, in a depth direction, in areas corresponding with the at least two of the plurality of zones; and d) partially further etching the target film after the film has been formed on the recess of the target film by a plasma generated from a third gas different from the second gas.
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November 20, 2020
July 5, 2022
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